Hydraulic extrusion presses



1967 R. H. GREEN ETAL HYDRAULIC EXTRUSION PRESSES 5 Sheets-Sheet 1 Filed Jan. 9, 1964 INVENTORS BY Mir);

ATTQENEVS 8- 8, 1957 R. H. GREEN ETAL 3,334,507

HYDRAULIC EXTRUS ION PRES SES Filed Jan. 9, 1964' 3 Sheets-Sheet 2 INVENTORS TQQ NEWS g- 3, 1967 R. H. GREEN, ETAL HYDRAULIC EXTRUSION PRESSES 5 Sheet$ $heet 5 Filed Jan. 9, 1964 INVENTORS mmmzw I ATTORN EYJ United States Patent 3,334,507 HYDRAULIC EXTRUSION PRESSES Ronald Harry Green, Gloucester, and Sydney Frederick Jenkins, Brockworth, Gloucester, England, assignors to Fielding & Platt Limited, Gloucester, England, a British company Filed Jan. 9, 1964, Ser. No. 336,759 Claims priority, application Great Britain, Jan. 11, 1963, 1,432/ 63; Aug. 30, 1963, 34,465/ 63 6 Claims. (Cl. 72-272) This invention relates to hydraulic extrusion presses and is more particularly concerned with the mounting of the billet containers in such presses.

The object of the invention is to provide an improved form of mounting which affords a rigid guiding of the container during axial movement and permits a high degree of accuracy to be obtained in the extrusion of, for

example, tubing. A further object of the invention is to facilitate manufacture and also the adjustment and alignment of the cooperating parts.

In conventional container guiding arrangements, the weight of the container mass and its housing is generally relied upon to keep the container guides securely riding on the guiding surfaces. It is not usual in a horizontal press to apply any form of restraint against the lifting of the container. When several rams are used in the axial movement of the container housing and Where the press is to be used for the production of very accurate tubes, it is desirable to hold the container in its axial position against movement in any direction except the axial one.

A factor which detracts from the accuracy of any press is that usually containers are guided on bedplates which run between the two main housings of the press. These bedplates are of a very light construction and although attached to the main housings, cannot be considered as rigidly attached to them.

According to the present invention there is provided a billet container mounting arrangement for a hydraulic extrusion press including guiding surfaces on which the container is supported and is movable only in an axial direction, said guiding surfaces being arranged and adapted to lie parallel to radial lines of symmetry of the container.

In a particular construction of press embodying the invention, the main end housing of the press is provided with cast on projections which afford the guiding surfaces and the container is formed or provided with, four radially extending projections constituting lugs which engage the guiding surfaces, or are providedwith members which engage those surfaces. The members referred to may be in the form of guide blocks adjustably mounted to ensure that the surfaces engaging their guiding surfaces are flat under all conditions.

In an alternative construction of container mounting arrangement according to the invention, the guiding surfaces for the billet container are formed or provided on extension members formed separately from and independently adjustable with respect to the main end housing.

Two forms of container guiding mounting assembly will now be described by way of example with reference to the accompanying drawings in which:

FIGURE 1 is a front elevation of a container mounting shown partly in section,

FIGURE 2 shows on a smaller scale than FIGURE 1 a side elevation in section of a portion only of the end housing of a press showing an end housing extension member and co-operating parts; and

FIGURE 3 is a sectional end elevation of the upper part of FIGURE 2 to a still smaller scale and shows also the corresponding parts below the horizontal centerline. The parts shown on the lefthand side of the verti- 1 3,334,507 Patented Aug. 8, 1967 cal center-line of FIGURE 3 are repeated on the righthand side although not shown.

Referring to FIGURE 1 of the drawings, the base of the press is indicated generally at 1 and the end housing is generally indicated at 2. The billet container 3 has integrally cast with it four lugs 4 which receive tie rods 5 to facilitate connection with container sealing and unsealing cylinders, not shown. The die slide 6 and container quick release means 7 are shown in the drawing but form no part of the present invention.

The press columns 8 tie the end housing to the cylinder housing, not shown, and the end housing has four cylindrical projections or heavy bosses 9 each provided with a flat container guiding surface 10 upon which seats a guide block 11 having a flat end face. Each guide block forms part of an assembly which provides for adjustment of the billet container to ensure that the guiding lugs 4 are as near as possible symmetrical about a radial center line of the container, Thus, the extension 12 of of each lug houses a steel screw 13, the spherical end 14 of which shown only in the section view of one of the extensions 12, seats in a correspondingly shaped recess in the guide block 11. The screw 13 passes through a non-ferrous bushing 15 formed with a shoulder 16 which engages an abutment 17 within the extension 12. A nut 18 enables the screw 13 to be secured in any selected position.

While the provision of the flat guide blocks 11 and guiding surfaces 10 restrain the container from movement in any direction other than axial with respect to the press, it is also essential for the production of accurate tubes to, ensure that when the container is heated or run at different heating temperatures, the expansion of the container housing should as far as possible be self-compensating so that the center-line of the container bore is always co-axial with the center-line of the press and die. The desired condition referred to is achieved, as just indicated, by ensuring that the guiding lugs 4 on the container housing are as near symmetrical as possible about a radial center-line of the container housing. Under all temperatures the lugs will expand radially outwards and if the lug casting is symmetrical about the center-line, its expansion will also be parallel to the center-line and if, in addition, the guiding surface 10 is also parallel to the radial center-line, then die guiding clearances will be maintained despite this expansion. The guide blocks 11 are in effect spherically mounted due to the provision of the spherically ended screws 13 so that a flat face bearing is maintained under all conditions. Adjustment of the screws 13 enables the whole container 3 to be adjusted to the center-line of the press.

The combination of a steel screw and non-ferrous bushing affords means for effecting compensation for heat expansion across a lug, that is to say, along the center-line of the screws 13. The position of the shoulder 16 and the position of the threaded portion 19 inside the bushing are so arranged that the expansion of the bushing away from the housing shoulder is exactly compensated by expansion of the spherically seated screw from the screwed portion of the bushing in the opposite direction. If the expansion of the bushing from the shoulder is equal to the expansion of the steel screw from the screwed portion of the bushing, the movement of the guiding surface indicated by the dimension Y will be constant for all temperatures. In order to compensate for expansion in the lug itself the shoulder of the bushing should be positioned as near as possible to the center-line CL. of the lug. The construction described ensures that any expansion of the components in the screw adjustment assembly can be controlled so that the wearing surface 3 of the guide block itself maintains a constant position from the center-line of the lugs.

Referring now to FIGURES 2 and 3, the billet container 3 has integrally cast with it lugs 4 which receive tie rods 5 to facilitate connection with container sealing and unsealing cylinders, not shown. Columns 8 tie the end housing to the cylinder housing, not shown, and in carrying out this modification of the invention, each of the parts 9 equivalent to the four cylindrical projections or heavy bosses 9 shown in FIGURE 1 is formed with a recess within which a cylindrical extension 20 is assembled. The columns 8 pass through the extensions 20, clamping nuts 21 being provided and to ensure tight clamping the columns 8 are prestressed. The prestressing can be effected for example by using the press main ram under power to stretch the columns 8 when by so doing a small gap is created between the nut 21 and the extension 20. If the nut 21 is then tightened to close the gap, the assembly of the extension in the end housing can be said to be in a prestressed or pre-tensioned condition when the press is not under load. Alternatively, the columns 8 can be prestressed by heating them either through holes in the end housing 2 or by placing an electrical resistance heater in a short bore up the center of the column thus creating an extension of the column under heat and again forming a gap between the nut 21 and extension 20. On closure of the gap by tightening up the nut the column will be in tension holding the extension 20 tightly against the end housing 2. The electrical heater would, of course, be removed after the necessary heating of the column had been carried out.

The guiding surfaces 10 are formed on the extensions 20 and it will be seen that because of the extensions 20 are initially supported from the main frame of the end housing, they can be rotated relatively to their recesses and SO permit adjustment of the inclination of the guiding surfaces with respect to the co-operating surfaces of the guide blocks 11. To enable the adjustment to be as accurate as possible, screws 22 on fixed mountings and having locking nuts are provided one on each side of and in contact with a lug 23 of each extension 20. Angular adjustment of the extension about its axis is effected by rotation of the screws.

The advantage of the arrangement described is that it is possible to rotate the extension within its recess at the erection stage of the press in order to bring the guiding surface machined on its exterior into the optimum position for container guiding. When that position has been reached, the extension can be locked securely.

We claim:

1. A billet container mounting arrangement for a hydraulic extrusion press including guiding surfaces on which the container is supported and is movable only in an axial direction, said guiding surfaces being arranged and adapted to lie parallel to radial lines of the container, said guiding surfaces being symmetrically arranged on the opposite sides of both a first plane through the axis of the container and a second plane through such axis, said second plane being normal to said first plane.

2. A billet container mounting arrangement for a hy-' draulic extrusion press including guiding surfaces on which the container is supported and is movable only in an axial direction, said guiding surfaces being formed on extensions of the main end housing of the press and being arranged and adapted to lie parallel to radial lines of the container, said guiding surfaces being symmetrically arranged on opposite sides of both a first plane through the axis of the container and a second plane through such axis, said second plane being normal to said first plane.

3. A billet container mounting arrangement according to claim 2 in which the main end housing of the press is provided with cast on projections which afford the guiding surfaces and the container has four radially extending projections constituting lugs provided with members which engage the guiding surfaces.

4. A billet container mounting arrangement as claimed in claim 3 in which the members engaging the guiding surfaces are adjustably mounted on the lugs.

5. A billet container mounting arrangement as claimed in claim 4 in which each adjustable mounting includes a non-ferrous bushing mounted in each lug and a ferrous adjustment screw passing therethrough, the coefficients of expansion of the screw and bushing and the geometry of the adjustable mounting being selected to ensure that the distance between the radial lines of the container passing through the lugs and the guiding surface is constant under all working temperatures.

6. A billet container mounting arrangement according to claim 1 in which the guiding surfaces are provided with extension members formed separately from and independently adjustable with respect to the main end housing and in which the guiding surfaces are provided.

References Cited UNITED STATES PATENTS 2,732,938 1/1956 Albers 72-272 2,923,407 2/1960 Billen 72272 FOREIGN PATENTS 969,579 6/ 1958 Germany. 335,124 9/1930 Great Britain.

CHARLES W. LANHAM, Primary Examiner.

H. D. HOINKES, Assistant Examiner. 

1. A BILLET CONTAINER MOUNTING ARRANGEMENT FOR A HYDRAULIC EXTTRUSION PRESS INCLUDING GUIDING SURFACES ON WHICH THE CONTAINER IS SUPPORTED AND IS MOVABLE ONLY IN AN AXIAL DIRECTION, SAID GUIDING SURFACES BEING ARRANGED AND ADAPTED TO LIE PARALLEL TO RADIAL LINES OF THE CONTAINER, SAID GUIDING SURFACES BEING SYMMETRICALLY ARRANGED ON THE OPPOSITE SIDES OF BOTH A FIRST PLANE THROUGH THE AXIS OF THE CONTAINER AND A SECOND PLANE THROUGH SUCH AXIS, SAID SECOND PLANE BEING NORMAL TO SAID FIRST PLANE. 